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在 2 5± 0 .1℃ ,I(KNO3) =0 .1 0 mol/ L ,p H=6 .5～ 9(5 0 mmol/ L缓冲溶液 )条件下 ,用分光光度法测定了含醇羟基和酚羟基链型氮氧杂配体 N,N -二 -(2 -羟乙基 ) -乙二胺 (L1)和 N-(2 -羟基苄基 ) -3-氨基 -1 -丙醇 (HL2 )的 Cu( )配合物及 N -(2 -羟乙基 ) -N -(2 -羟基苄基 ) -乙二胺 (HL3)和 N -(2 -羟乙基 ) -二乙三胺(L4 )的 Zn( )配合物催化对硝基苯酚乙酸酯 (NA)水解动力学 ,得到了 NA酯催化水解二级反应速率常数k C.结果表明 ,在中性 p H值附近生成的配位烷氧负离子 Cu( )…… - OR和 Zn( )…… - OR均为很好的亲核试剂 .配合物对 NA酯水解有亲核试剂进攻和金属离子作为 L ewis酸活化底物的双重催化作用 ,k C 值可分别达到 6 .72× 1 0 - 2 ,0 .1 2 6 ,4.5 5× 1 0 - 2 和 7.6 6× 1 0 - 2 mol- 1·L· s- 1.
Under the conditions of 25 ± 0.1 ℃, I (KNO3) = 0.100 mol / L, p H = 6.5-9 (50 mmol / L buffer solution) Hydroxyl and Phenolic Hydroxyl Chain N - Oxadiazoles N, N - Bis - (2 - Hydroxyethyl) - Ethylenediamine (L1) and N- (2 - Hydroxybenzyl) -3 - Amino - 1 - Propanol (2 - hydroxyethyl) -N - (2 - hydroxybenzyl) - ethylenediamine (HL3) and N - (2 - hydroxyethyl) The kinetics of p-nitrophenol acetate (NA) catalysis catalyzed by the Zn () complex of amine (L4) gave the second-order rate constant kC of NA ester catalyzed hydrolysis. The results showed that the neutral p H value The complexation of alkoxide anions Cu () ... - OR and Zn () ... - OR are good nucleophiles.The complexes have nucleophilic attack on NA ester hydrolysis and metal ions as Lewis acid activation bottom The results showed that the value of k C could reach 6 .72 × 10-2, 0.1 2 6, 4.5 5 × 10-2 and 7.6 6 × 10-2 mol -1 · s · s -1, respectively. 1.